<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>04_执行上下文栈2</title>
</head>
<body>
<!--
1. 依次输出什么?
  gb: undefined
  fb: 1
  fb: 2
  fb: 3
  fe: 3
  fe: 2
  fe: 1
  ge: 1
2. 整个过程中产生了几个执行上下文?  5
-->
<script type="text/javascript">
  console.log('gb: '+ i)
  var i = 1
  foo(1)
  function foo(i) {
    if (i == 4) {
      return
    }
    console.log('fb:' + i)
    foo(i + 1) //递归调用: 在函数内部调用自己
    console.log('fe:' + i)
  }
  console.log('ge: ' + i)
</script>
</body>
</html>